Diarylborinic acids (Ar2BOH) catalyze the C3-selective ring opening of 3,4-epoxy alcohols with aniline, dialkylamine and arenethiol nucleophiles. The regiochemical outcome is consistent with a catalytic tethering mechanism in which the borinic acid interacts with both the electrophile and the nucleophile. The rate acceleration resulting from this induced intramolecularity effect is sufficient to overcome
二芳基
硼酸(Ar 2 BOH)与
苯胺,二烷基胺和槟榔亲核试剂一起催化3,4-环氧醇的C3选择性开环。区域
化学结果与催化性束缚机制一致,在该机制中,
硼酸与亲电试剂和亲核试剂都相互作用。由这种诱导的分子内效应产生的速率加速足以克服空间偏倚,否则将有利于取代的环氧醇的C 4选择性打开。